sub do_while {
use Fcntl qw(:seek);
#count lines and rewind
while(<FILE0>){$linetotal++}
  seek FILE0, 0, SEEK_SET or die "Cannot rewind file: $!";

while(<FILE1>){$linetotal++} 
  seek FILE1, 0, SEEK_SET or die "Cannot rewind file: $!";
              
while(<FILE2>){$linetotal++} 
  seek FILE2, 0, SEEK_SET or die "Cannot rewind file: $!";

print "$linetotal\n";
             
$progressbar = $main->ProgressBar(
       -length => 200,  # Actually width 
       -width  => 20,   # Actually height 
       -gap    => 0,
       -value  => 0,
       -colors => [0, 'pink'],
          )->pack(-pady => 5, -padx => 5);     

    while (<FILE0>) {
        my $line = $_;
        chomp($line);
        do_opt0($line);
        if ( $line ne $token ) {
            print SFILE "$token";
        }
    $progressbar->value($progressbar->value + (100/$linetotal) );
    $main->update;
       }

    while (<FILE1>) {
        my $line = $_;
        chomp($line);
        do_opt1($line);
        if ( $line ne $token ) {
            print SFILE "$token";
        }
    $progressbar->value($progressbar->value + (100/$linetotal) );
    $main->update;
    }

    while (<FILE2>) {
        my $line = $_;
        chomp($line);
        do_opt2($line);
        if ( $line ne $token ) {
            print SFILE "$token";
        }
    $progressbar->value($progressbar->value + (100/$linetotal) );
    $main->update;
    }
}